1 /*
   2  * Copyright (c) 2008, 2009, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.nio.ch;
  27 
  28 import java.nio.channels.*;
  29 import java.nio.channels.spi.AsynchronousChannelProvider;
  30 import java.util.concurrent.ExecutorService;
  31 import java.util.concurrent.ThreadFactory;
  32 import java.io.IOException;
  33 
  34 public class WindowsAsynchronousChannelProvider
  35     extends AsynchronousChannelProvider
  36 {
  37     private static volatile Iocp defaultIocp;
  38 
  39     public WindowsAsynchronousChannelProvider() {
  40         // nothing to do
  41     }
  42 
  43     private Iocp defaultIocp() throws IOException {
  44         if (defaultIocp == null) {
  45             synchronized (WindowsAsynchronousChannelProvider.class) {
  46                 if (defaultIocp == null) {
  47                     // default thread pool may be shared with AsynchronousFileChannels
  48                     defaultIocp = new Iocp(this, ThreadPool.getDefault()).start();
  49                 }
  50             }
  51         }
  52         return defaultIocp;
  53     }
  54 
  55     @Override
  56     public AsynchronousChannelGroup openAsynchronousChannelGroup(int nThreads, ThreadFactory factory)
  57         throws IOException
  58     {
  59         return new Iocp(this, ThreadPool.create(nThreads, factory)).start();
  60     }
  61 
  62     @Override
  63     public AsynchronousChannelGroup openAsynchronousChannelGroup(ExecutorService executor, int initialSize)
  64         throws IOException
  65     {
  66         return new Iocp(this, ThreadPool.wrap(executor, initialSize)).start();
  67     }
  68 
  69     private Iocp toIocp(AsynchronousChannelGroup group) throws IOException {
  70         if (group == null) {
  71             return defaultIocp();
  72         } else {
  73             if (!(group instanceof Iocp))
  74                 throw new IllegalChannelGroupException();
  75             return (Iocp)group;
  76         }
  77     }
  78 
  79     @Override
  80     public AsynchronousServerSocketChannel openAsynchronousServerSocketChannel(AsynchronousChannelGroup group)
  81         throws IOException
  82     {
  83         return new WindowsAsynchronousServerSocketChannelImpl(toIocp(group));
  84     }
  85 
  86     @Override
  87     public AsynchronousSocketChannel openAsynchronousSocketChannel(AsynchronousChannelGroup group)
  88         throws IOException
  89     {
  90         return new WindowsAsynchronousSocketChannelImpl(toIocp(group));
  91     }
  92 }